Hi, i recently resealed my 1.8 pump,, kit# X2421aa000, was a good # and it had a o ring in between the plate and front body. the screws came out but was very tight. my 84 parts book has the pic you posted. i'm pretty sure the turbo is same as std 1.8 , part# for the oring is 8069 49030, size is 49.7x 3.5 , it was included in the kit. also another oring 8069 15050, 15.5x 1.5 is in there. it is behind the plate too, and a spring and ball.. your pic does show the extra oring. but my book also does not show it on the turbo page,, i think it's in there.