I just replaced the mounts on my Yanmar 3HM35F two months ago. I did all the work my self so I have taken the hard road, but it is well worth it. I know the procedures well and can allign the engine again with no problems. Installing the new mounts is not bad. The engine re-allignment was the most difficult part for us.
I researched the availble aftermarket mounts and decided to use the Yanmar mounts. In the end, it was an easy choice. I checked with three Yanmar distributors, a Yanmar mechanic, and my manual and all confirmed the 3HM35F uses four #100 mounts. This is important because some of the small engines used different mounts front and back. I can give you the Yanmar part # but I don't have it in front of me right now.
Please forgive me, but it is late and my wife and I have been traveling in our boat up the Tombigbee River for the last seven days to get out of harms way for hurricane season. It would take me several hours to type a proper reply to your questions. I would be happy to talk to you about my experiences and how we did things. If you would like to discuss it please send me your phone numner and I can call you tomorrow afternoon. My e-mail address is firstname.lastname@example.org
I talked to several mechanics before undertaking the project. I had one mechanic flat out lie to me and try to rip me off. It will be a long frustrating processs, but I am so glad I did it myself.
1988 Crealock 34, #95