I’m assuming you want to port it yourself.
105.5/120/78. Widen the exhaust.
Only model where I prefer the meteor piston over OEM, it’s actually a gram lighter. Use oem pin.
30 from band. Lose the BG. Set squish at 18.
Lower the intake floor and keep the factory width.
Advance the timing 1/2 the key. If you don’t have a decomp, you may have to dial that back. I had a real biter once, had to dial it back.
Open the area under the stock muffler deflector. Trim or fold the teeth and pry it open to a hemisphere. If you don’t have the removable deflector type, cut the oem w tin snips and fold back/braze when done.
You’ll need an 87 carb or 199 conversion. Will run well with a 120/144, but not as well-I can personally attest to this.
Many threads here on 262 builds and 199 conversions. Just use the search function.
Do a thread if you can. IMHO, we need more.
Good Luck.