Pearson 365 and 367

I plan to re-power my 1976 P365, Hull #30. 
Current power is the original Westerbeke 4-107.
Transmission is a Borg Warner Velvet Drive model 10-17-004.
V-Drive is a Walter model RV-10.
Both transmission and v-drive have been recently rebuilt.
I hope to install a Yanmar 3JH5 mounted to the existing velvet drive.
Has anyone performed this install and/or know of a reason not to try?

Please add Anne B to the list. She is a 1976 Cutter/Ketch Hull # 30.
Her owners are Marty and Carol Southard.
She is currently berthed in the Gulfport (FL) Municipal Marina but has been known to wander off Florida's West Coast and the Keys.