I might swap my good low mileage motor for a blown motor from my buddy coupled with some cash.

The plan is to use the money to rebuild and improve the blow motor. What internal mods would be worthwile?

Big Bore? What pistons are available and how big can you get while retaining reliability? Would the jetting then become a nightmare?

Porting? I can de-burr and polish intake and ehaust runners but should I have a pro dig them out? If so, who? Would the jetting then become a nightmare?

5 angle valve job? Is it worth asking for at the machine shop?

Increased compression? Highest I can run with 92 octane?