123 Chassis rear control arm replacement

[klataklatacoupe]

The rear control arm on my '84 300 cdt has been in need of replacement since i got it. i've welded it several times to keep it on the road and have been looking for a replacement for years in local bone yards. i recently came across a '76 280 4dr sedan. im not sure of the chassis number, i think its a 116. the control arm looks the same, i was wondering if any one can confirm this. any input would be appreciated, thanks.