Jim, if you haven't seen this article on the 1987 300D yet, make sure you read it:
http://www.w124performance.com/docs/mb/articles/124.1x3_buying_tips.txt
About power gains, first get the car to perform as Mercedes intended... a 0-60 time in the 10-12 second range. If you want more power, then there are multiple options beyond that, from 20% to 200% power increase - just depends on the depth of your wallet.
Please take the recommendations to "just ditch the ALDA" with a large grain of salt. I'm tired if arguing with the guys who do this... if they want to, and accept the drawbacks, fine... but telling everyone worldwide to toss the ALDA is idiocy. ALDA removal is not a magic pill that cures all evils. It also will not increase your peak power output one bit... you need to tweak internal ajustments to accomplish that.
:fork_off: