Thanks, I've my moments
my opinion is that you get the best result by using separate round piece and wheeling, then press it and weld them together.
I have made many 3" ball from 20 gauge and there I noticed that starting point have to be round piece. That way the streching is even so the deformation would be less. Try your self and post results. The ball is made from two pieces, tig'ed together.
Check the balls over the stacks, as an custom fabrication company cant just use tennisballs.
I got that car finished about a month ago. 750hp 615 + PG got a II price at our autum international yankeecar show. Off topic, sorry..