When I inspect the watch based on the provided pics, the question to ask is does the overall look and condition correlate with all components? So, lets start with the case, looks like it has been recently recut quite nicely. There is no catering around the lug holes which is a big plus. The reference number between the lugs looks extremely clean, but the type font is consistent with 8m serial GMTs.
The dial also looks nice and is period correct for this reference. I can't tell if it has chips, blemishes or missing lume which is extremely important. The hands are not attractive and is what holds this watch back. I suspect, they were relumed in past; the composition of the 24hr hand is different and the lume on the hour hand is cracking which is indicative of cheap relume job. Regardless, I would be looking for genuine replacement for the second hand as its not worth salvaging and reluming the other 3 hands to color match the dial.
Lastly, the insert also looks to be period correct and would be worth swamping with a nicer genuine Redback to complete the make over. These items won't come cheap, but will make this watch quite attractive.
Best of luck.
