If the early crossmember is the earliest version, there are several differences.

To start, 1969-1973 1800 crossmembers have brackets for dual brake hoses on each side, but you can cut those off and weld them onto the earlier crossmember.

The earliest version of the 1800 crossmember uses a now fairly rare lower control arm that mounts the same as the upper control arm, with U-bolts instead of a large bolt like the later crossmembers.

The early upper control arms use a different, but now available upper ball joint.

And if you happen to be unlucky and not know like 1 of my customers and it turns out the early crossmember he bought wasn't even for his early P1800, but rather came out of an B16 equipped 122 which used the same style of body mounting all of the 1800 used, but the motor mount brackets on the crossmember are installed differently and caused his engine to hit the hood.

I recommend you just rebuild yours, but do look for bracket failure at the supports for the lower pivot bolt. It is common to find these cracked and in worse cases damaged so badly, they can't be easily repaired. Also look closely at the area around each upper shock mount hole. Cracks there are also common.
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Eric
Hi Performance Automotive Service (formerly OVO or Old Volvos Only)
Torrance, CA 90502