It's possible to boost your EJ22E 5psi with no additional engine management. Haven't done it myself but there are plenty of threads on RS25 and NASIOC (in fact there is a specific forum on NASIOC for na engines with bolt on fi).
No need for a fmic for that level of boost, but for a tmic you'd need a scooped hood or cut a hole in yours and install a wrx scoop or something. That being said you could probably get away with no intercooler if you use a VF11 and even a TDO4 under low boost. The 90-94 tleggys w/vf11 did not come with tmic and run 8.7 psi stock.
One thing to keep in mind is depending on what year your 22e is is compression. Phase 2 have high compression (up to 10:1 iirc) so detonation is a real possibility. Also your engine is old and I'd be concerned about possible hg issues.
You will need a notched crossmember for the up pipe to clear. A direct fit is a xmember from a 90-94 tleggy but you have welding skills so you could notch yours and reinforce it. You will also need a downpipe. Stock injectors will be able to handle your fueling needs. Also you will need to tap your heads for oil and coolant to run the turbo.
Stock fuel pump will work but maybe yours is old. If you replace it I recommend a Walbro 255. A complete pump and kit is only $100 from Amazon.
Of course there is more to it but that's the jist of it and I have to go to work, lol.
Check your vacuum lines, plugs, pcv valve, fuel filter, wires, clean the tb to see if you can get your car running better before you go and do something crazy!