Here is numbers from my HX 50 dataplate
Assy: 3591777
Serial: H010607571
Customer: 1423037
Model: HX50-1378395
Exhaust pinwheel size are :
ID-> 77mm /3,03 inch
OD -> 86mm /3,385 inch
And here is numbers from exhaust housing:
3537412- 02
25 129 TF 2
Exhaust housing is bolted (6 - bolts) to bearing housing.