Hi Tim,
I can appreciate your creativity in designing and building your own float adjustment tool, But there is an easier way. Without having to re-design the wheel so to speak, Gene Berg offers a tool (#GB552) which takes all the guess work out of setting float levels for the 48 IDA.
Float level is critical to the 48 IDA, get this wrong and you will hate Webers!
Anyway, I use this tool exclusively to set float levels on my carbs. No guess work. I have a set of early serial numbered carbs from approximately 1966 stamped 48IDA with serial #’s 931, 935, 1031 and 1035 which they have not been modified for/with the 3rd progression holes.
Back to float adjustments, I also use these 2 spacers and nuts (in the photos) due to the studs where I mount the needle/seat to the plate then attach it to the carb. Float levels are measured by inverting (holding and turning the carb upside down) then measuring how far the float hangs down once it rests against the needle/seat assembly. All I do is adjust/bend the tab on the float to achieve the required 5.5 to 6.0 spec (2nd part of the tool, see pic) so when I hold the other tool against the body I’m within tolerance per the Gene Berg instructions. Personally, the tool is a vital investment and not too expensive for what it does, it's easy to use too. I still have hair on my head!
Happy Tuning,
~Earl J
ps. By the way Welcome to the CC forum!