Big Block K Frame Identification

Hello All,

I have started to dive into my 1969 Dart project 6 cyl to 383 big block. Have done a lot of reading here on the site and have obtained a lot of good information.

I supposedly purchased a new never used direct connection big block k-frame with spool mounts. When I compare my K-Frame to other pictures of direct connection k-frames on this forum and the web, they look different than mine. I cant make out the numbers on my K-Frame very well but, they seem be 484MN28. I have attached pictures in hopes that someone on the forum can identify my k-frame.

thanks