Good advice listed above. Be aware that nothing from the 235-6
can be used for the V-8 conversion with the possible exception of the clutch, depending on what V-8 flywheel you use. The V-8 conversion is one of the most popular subjects covered on this site. Lots of information here. I made up a spreadsheet several years ago listing the parts used in the conversion. If you think it is something you can use, send me an email and I'll send it to you. Depending on where you are in "socal" you could also look at mine.
Fred





1956 3100 Pickup/Red/350/3sp OD/PS/Disc Brakes
1957 Bel Air Sport Coupe/Red/355/TH350/PS/Disc Brakes
2017 Silverado LT Single Cab SB/Black/5.3/6 Speed Trans
1947 Willys CJ2A w/F-Head engine