1980 KZ750 LTD H - help getting dust seal on to the caliper

Hey people,
Have been working the front brakes draining and cleaning and rebuilding. I'm installing the dust seal over the piston and man it's giving me such a hard time. Is there a trick or tool to get this bugger back in its groove? Thanks in advance for advice, everyone is so helpful here.

Not wanting to state the obvious but do you have the correct size? Coincidentally I did one also today on a 1000 LTD. It has 38mm pistons but some of these bikes/models are 40mm.

My method was to remove the dust seal retainer, fit the seal over the retainer, fit the seal over the piston, then install the piston in to the calliper with seal and retainer already on the piston, then push home the retainer.

Getting the seal over the piston should not be awkward at all.

Hey Bob,
It's the original piston and dust seal they looked good no pitting or scratches on the piston, so I didn't replace them and think the sizing is correct. This is my first bike, and therefore my first attempt at anything like this. Sounds like technique is going to be the winner. I'll try your method, thanks much!

I slide the dust boot over the piston, positioning it at the very bottom. Then install the lip of the boot into the mating groove in the caliper body and lastly push the piston into the bore.

Thanks Nessism, this method worked for me, It also helps that I decided to replace the boots. Appreciate the advice.