L/C 430 right crank bearing

Exactly!
I've looked through the service bulletins in the past, mostly looking for Auto stuff, but looks like I need to do some more research.
Thanks for the reminder.

OK, I searched the service bulletins for a 430 porting reference.

I only found a March '82 bulletin #8-097, page 130 of the 8-service_bulletins.pdf file on this Cafe H page, "8-001 to 8-149 bulletins":
http://www.cafehusky.com/threads/vintage-husqvarna-service-bulletins.1312/

So this performance mod, a 4.5mm more opening on piston was still good for a '88 430?

Yes, from what I've learned on here. There are others on here that have done this as well. I am not the first by any means. I also did a little on the cyl. intake but not as much as in the diagram. Glad you found it. The bike shreds the back tire loose even easier than before and pulls harder at the top end.

Cool. I'll have to try the porting for my 430.
The bulletin mentions other mods. Did you do those?
Like the exhaust pipe mod? I wonder how that changes the power band?

No, I already had an Uptite racing pipe so I didn't change that. I raised the exhaust port, smoothed out the exh. port with a sanding flap wheel, "winged" the intake ports a little. knife edged the center web in the intake, cleaned up & knife edged the divider in the transfer ports & trimmed the cyl. base gasket so it didn't hang over the edge & protrude into the transfer ports. I also raised the ports in the piston.