A couple of things....Generally an 88-94 EFI 2.3L will not have the ability to install a mech fuel pump. The aux shaft may have the lobe (at least the 88's)..but the opening into the aux housing will not be machined to allow you to use a pump. The bolt holes should be there...but not the larger opening for the pump actuating lever. The exception will be most turbo'd motors for some reason. They all seem to have the hole in the block for the pump. (maybe because marine/industrial applications use the turbo block?) You could use an 88-94 block but "poke" a hole there and use a pump I'm sure. Just be sure your aux shaft has the lobe for the pump drive or be prepared to buy another one.
FYI the OMC marine 2.3L advertises 120HP...with a carb...you CAN get good HP with a carb if you work at it...but be prepared tof some head work, and cam perhaps along with some carb tuning. Thing like shaving the head, advancing the cam timing, and higher lift cams make the engine come alive....but grab a spare head while ur at it...they can be bought new but are somewhat spendy..
The stock 2.3L cast crank and rods will support 300HP or more if ur careful...
There doesn't seem to be great advantage to the 2.5 crank conversion with all that is involved...
2.0's can run too....find a 2barrel version manifold for yours, and get a factory ford header....(mid 90's)...and make some fun...
have fun....