Has anyone fitted an aftermarket steering wheel?
If so, could it be bolted to the existing hub or was an adaptor required,
and did it have a horn button?

Yes it can be done.

An adapter is required.

A search on Google showed adapters for the PV most of which had holes to use several different steering wheel bolt patterns.

The spacer that also cancels the turn signal switch may need to be modified or replaced with the 122 version as the PV spacer has a nub that mates to a notch in the back of the original steering wheel while the 122 spacer has a notch for the pin on the back of a 122 steering wheel.

The only time we did a 544 conversion, the customer supplied the steering wheel and adapter. The adapter wasn't made correctly and had to be modified so the steering wheel didn't wobble and we had to relocate the pin for the spacer/turn signal canceller. IIRC, we had the hole for the shaft machined to remove some of the splines inside the adapter so that the shaft could go in farther.

I can't remember the brand of steering wheel or adapter the customer supplied, but it wasn't a Grant.

The spline count is the same as a 122 and Grant used to make an adapter for a 122, but, but never listed it as fitting a PV, probably because of the spacer issue. VP used to offer the Grant adapter for the 122, but it's no longer on their website.

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Eric
Hi Performance Automotive Service (formerly OVO or Old Volvos Only)
Torrance, CA 90502
hiperformanceautoservice.com or oldvolvosonly.com

When using a Grant on an Amazon I believe that a Jeep adaptor can be used. Check before you buy unless it's easy to return.

https://www.ebay.com/itm/232879209389?chn=ps&norover=1&mkscid=101&itemid=232879209389&targetid=1645685074768&device=c&mktype=pla&googleloc=9003733&poi=&campaignid=20133407470&mkgroupid=147476396765&rlsatarget=pla-1645685074768&abcId=9312979&merchantid=102002334&gad_source=1

Try this adapter. I believe this is the one I bought years ago from VP Autoparts for my 122. Works great. I am using a LeCarra wheel with it.

I use a Lecarra wheel as well, adapter is a modified from a 122, works well and looks good

Micheal,
I realize that it's been a while, but I've now got everything assembled and am looking for a 122 spacer. Can you tell me what modification was needed to mate it to the signal switch?

I used to have a Grant mounting kit and had a LeCarra Grant To LeCarra adapter. I found that the one I later bought was a much better fitting steering wheel adapter.