My van (Gloria) finally runs and drives!

I need a general opinion on how it "should drive".
I know that it’s the slowest thing since the snale but what do you think of this:-
Engine starts well and runs smooth, on the flat will make it to about 55 MPH but yesterday when I was going up a fairly steep hill (the on near Lanchester to Stanley in Durham for those local) I had to drop all the way down to 1st gear and the max I could get was 15 maybe 20 mph.
is that normal on a steep hill?
So I’m left thinking that the pump timing may be out a bit since it starts and runs ok with no smoke. My initial idea was that it could need to be advanced a bit so I tried this and I could hear a bit of nock (more like marbles) this would increase the more advanced I made it so I called it a night.
What do you all think, give it a little more advance and have a tiny amount of that sound? Or maybe retard it a little more?
Any advice on what I would see/hear when too advanced and to retarded would be super as having it done by a garage is not on the cards at the moment.
Thanks agian Chaps!