Super Elite Crotch Strap too tight. HELP PLEASE!!!

I bought my 4 year old DS a super elite (prior to Huskys coming out). He is 32 pounds and has a very long torso. He was using a graco ultra cargo but his shoulders are now above the tallest notches. I put in his super elite, but the crotch strap seems very tight, and he is uncomfortable. I called britax, and they said NOT to move the strap out until he is 50lbs. I really want to move it, but am afraid this will be dangerous to my son.

I cannot use this seat with the crotch strap in this position, cause DS does not like it, and DH will go crazy I wasted all the money on it. ( I cant return it cause I bought it last year). I really have no other options but a booster due to DS shoulder height, and a booster is not an option cause DS will NOT sit still for more than 30 seconds. (I tried the marathon too, and his shoulders are above the heighest notch there too. UGH. Please Help.

ANY suggestions?

[Joolsplus2]

For my 40 pound 6 yo, we have threaded the crotch srap through the outer slit in the cover, and that made it more comfortable and easier to buckle...so it's still routed through the inside plastic slot in the seat, but is coming through the outside slit in the cover. It's worth a try, at least :(