Ok you really need to do some proper test like in way beyond monochrome
But if you don't wanna do that my advice would be use Iso 200 develop 15% less than stated by ilford with chosen developer. Then get a even textured surface evenly lit and point your spot meter at it and expose at zone 2 and then a zone 8 these zones should be lightest and darkest with texture.
But from my own experience you really need to do proper test also paper tests.
I would also for a quick paper test, develop a blank neg (this will give you film base + fog) and place it in your enlarger and print a test strip at 3 secs apart then develop as normal allow to dry and look for the time that is maximum black, then when your other tests are done print at this time and this will give you an idea what a zone two will look like and an 8, if the two is too dark try a different iso if the 8 is too light reduce dev time by 15% if its too dark increase dev time.
Then once that it done, go out take a pic without filter, bellows extension but with a good range of tones and try and print it. If all works out ok then you can go at and any mistakes you can at least narrow down a bit more.