I got a good deal at the LHS a couple of months back on a Seagull Mew Gull, now I need to decide on an engine for it. I have an OS91 (too small) and a DLE 30 a little to big. I am thinking of getting either an OS120 or a DLE 20. I like my DLE30 so much I'd like to get the DLE20 but the distance from the firewall to the prop drive washer is about 3" and the DLE20 is about 5" from the prop drive to the back of the carb. so I'm not sure how to handle this. Anyone got any ideas?

Use shorter standoffs and then relieve the firewall to clear the carb.

I see your a big fan of dle/2 stroke gassers.Mine has a saito 220 and balances well.