Should be a piecacake. Don't blind yourself with science. Below is a description of how I would do it based on how I do do it in a 30 foot five-tonner coming into a slip that is tighter than yours :-).
Like I, you have a right hand prop I gather. So item #1 is that you are doing the right thing by coming port side to. Item #2 is to make sure that you are properly PREPARED. I hope you have a gate in your life lines just aft of your main bulkhead. Having one facilitates swift, elegant
work which is what this situation calls for. Coming in, set your fenders. Open the port side gate. Belay a longish purpose specific line on your port midships cleat and bring it
OUTBOARD of all stanchions etc, to the
steering position and hang it where you can easily get at it, and in such a way that it won't snarl. This line is a purpose specific tool and not part of your normal dockline outfit.
Come in at about 30º to your slip, clearing the "stump" by a few inches. The
wind is your friend here, but of course you are maintaining steerageway so there shouldn't be an issue. As soon as your transom clears the stump, put 5º of starboard rudder on, and go astern at 1,800 RPM. This will lay you dead in the
water parallel to your slip, and with your midships cleat just about at the end of your slip.
Play in a systematic manner with the approach angle, the rudder deflection and the RPM making mental note of what you do until you can consistently lay the boat alongside 6" from the slip with the midships cleat just within the length of the slip. Practice doing this. A LOT :-)!
When you can do it WITHOUT FAIL, drop the BIGHT of your line over the cleat midway along the slip, haul taut and make the running end of the line fast aboard. There is a special technique for heaving a BIGHT of
rope so it will encircle a cleat. Learn to use that technique.
A towboat hitch over your sheet winch works wonderfully for making fast the running part. The cleat on your quarter will also do, if that's more convenient. When this is done to your satisfaction, Swiftly come to AHEAD 1,200 RPM leaving the rudder 5º to starboard. If you blow it, just go around again.
The boat will now, working against the line, draw herself into the dock. Your
head might blow off a little, but in a 5-tonner that doesn't matter as long as you are made fast! You can now step off through the gate, which will be very close to the dock, looking for all the world as if you knew what you were doing :-)!
Note that using this technique there is simply NO temptation to get off the boat until she is already made fast. There is no trick to moving a 5-tonner from the position your boat will now be in with the forepart sticking out beyond the slip, to the position you want her to be in. That's just a question setting and belaying your dock lines appropriately. You can, if you like, set a temporary "midships breast" at the pivot point even if you have to belay it at the foot of a stanchion. This will prevent the wind from taking her while you set your regular dock lines, and it will facilitate moving her incrementally using the engine.
This works in a slip that has
cleats to drop a bight of line over. If the slip has a bullrail, rather than
cleats, the situation is a little more difficult and not conducive to doing it on your lonesome.
My home slip has a bullrail. So far so good. It's dodgy, but by being prepared I've been able to come to "STOP" (i.e. neutral with the engine still running), step smartly off at the gate, and get my line around the bullrail, quick as a wink, with a round turn and two half hitches tied on the bight. Like I said: So far so good, but I don't like it. When I go to the boat again in a coupla weeks, I'll install a cleat on top of the bullrail so I can follow my own
advice :-)!
All the best
TrentePieds