been there done that...
Call Craig Conley at Paradise Wheels in California. He will be most helpful and give good advice.
I had a 60s era Paxton ball drive Paxton updated to VR4 racing specs on my SPF and 351 W with about 9-10 pounds of boost. The blower was fine but my engine blew ; due to wrong metal pistons, too high compression and too much boost for the engine internals. The engine was not what it had been represented to be when I bought it and I should have torn into it to see what it really was before i added the blower
The sound of that Paxton as it spooled up was outstanding, as was the kick when it threw you to the back of the seat on WOT hits to the accelerator pedal.
Alas, after 3000 mi the engine blew and I decided to not have a blower on the new one.
Costs. it aint cheap : $2500-3000 for the blower. Requires a blower friendly rebuilt carb to handle the boost. Custom bracketry most likely needed. a tight fit under the spf hood for routing of air intake hoses, especially over the valve covers. Special MSD ignition needed that retards the spark as the boost goes up, it must not get lean or whammo bammo- gotta keep the air to fuel ratio fat/rich for insurance. High output fuel pressure needed if ya dont have it . Other items perhaps unique to your engine install...like I had to relocate the remote
oil filter so it would clear the blower pulley, had to get a different crank pulley, yadda yadda. all said and done you can kiss $4-5K goodbye. lots of eyeball though and lots of fun, AS LONG AS YOUR ENGINE INTERNALS ARE SPECIFIC TO BEING BLOWER FRIENDLY.
See pics in my photo gallery, damn - I miss the looks and sound and kick of that blower . At the time the engine blew i had some pressing time committments for car events and opted to replace it with a crate motor vs a rebuild as i could be back on the road in one week vs several weeks-thus being able to attend my pre planned events.
There are some other blowers now on the market that might also have some 'ready to bolt on' 351w installation kits . If the kits will work on your engine and bay. mine had to be custom made except for one bracket from a 289/302 install kit that would work- several other brackets and spacers ( alternator had to be moved out from the engine to clear the blower pulley) .Other spacers/brackets had to be custom fit/made for me, all adding to the cost of install.
Good luck...and enjoy...but consider the total cost vs updgrading engine for what is the best bang for the buck for you ...Bill