SBEC part number identification.

1990 Daytona shelby TI auto. Since I've owned my car it has had the Sbec in it that was there when I bought the car. The person that purchased a mopar performance Sbec for it took the stick off and put it in a plastic notebook sheet with all the other under hood stickers. The sticker says P4532336 for off road use only.

Today I decided to swap in a stock SBEC I got out of a 90/91 spirit or shadow T1 auto at a yard. The number on it is 527(6) I think then 407. I am loving how this is making the car run. First thing I noticed is it doesn't have a super slow downrev/high idle after hitting the gas or coming to a coasting stop. Ok, I like that lol. I also noticed that when part throttle driving the MP SBEC would go rich like im at WOT as soon as it saw any boost. The stock one keeps floating back and forth on my a/f narrowband guage until a significant amount of boost/throttle or rpm. I bet this will help out my mpg a ton. Its really hard to drive without getting even 1 psi and having it go rich with the MP sbec. The stocker seems to idle/runn so much cleaner smoother as well. Anybody have any clue about these 2 Sbec's, couldn't find their numbers in the ecu number database here.