I am putting together my first build, and I need some help. I posted this on the Retro forum, but I  thought the guys on this forum might have some advice for me as well.

I have a SP1, (or maybe a M16), slick side upper with a large front pivot hole.

I want to mate it to a small hole Superior Arms lower.

I have looked at a couple of different options, but I would like to hear recommendations from somebody with some experience with this condition.

Thanks,

Mick

Hi you can get a reverse offset pin addaptor from bushmaster for less than $20. It allows you to mount a large hole upper to a small hole lower.

http://www.pkfirearms.com/store/get_items.aspx?type=0&term=39




Lower Receiver Accessories
Offset Bushing
Adapts large hole, Colt upper front pivot pin diameter (.312 ) to small hole lower pin diameter ( .250 ).  
Our Price: $3.00


this is what you need. i don't know of any other options.