Do I need to have velocity stacks inside the air cleaner on top of dual webers?

car will run without them

Is it better with them for any reason?

If yuv got big cc's and big cam and big heads then u might need them but if not i wouldnt bother,spend your money where yule get a bigger bang for your buck

I didnt run them on my 36's
You can but they may get in the way of the idle jets

36's are great - the idle jet is on the top.

IF you want then 40's will fit

I will be interested in your progress

I'll let you know how I go.
Could be interesting, I'm not the most mechanical person I know!
But I'll have a go anyway.