Title says it all.   Thanks for your help.

I really like the flat sided punches designed expressly for that purpose.  I also LOVE the starter punches Schuster makes.  They work awesome.

I'm thinking it's either 5/64" or 3/32".  Probably 3/32".

Schuster punches

Thank you Sir.  Is there a tool to support the little ears so I don't bust them off?  That would REALLY suck.

The ears or bosses on the bolt catch are pretty sturdy.  The concern with that roll pin is the punch slipping more than breaking the bosses.  It is a 3/32 punch and  yes, the slab side punch made for installing it and removing it is very useful.  Well worth the $15 (or $11 w/discount) at Brownells.

Breaking the ears on the trigger guard is more common.  Supporting the underside and keeping the trigger guard in place while tapping the roll pin is a good way to prevent breaking.  There are a lot of methods.  One is to use a 1/2" thick piece of wood and slide it under the guard area.  Here is a picture of a piece of plastic that is similar to using wood.  This block self aligns and has holes under the roll pin that you can't see for removing the roll pin.

Without a grip installed:



With a grip installed:



You might find protected vise grips or a c-clamp easier for the trigger guard, but they don't work as well on the bolt catch.

   

Just use a medium size nail set,........convave tip, works perfectly!

I used this for my latest build, and it was the easiest build ever.

Brownell's Bolt Catch Roll Pin Punch

I used needle nose to hold the pin and taped channel locks to squeeze it in there. Super easy.