Lets start with the big issue which came about when you increased the weight on the bow.
The arrows may be within the spine range but all that means is that they can be tuned with range of weight that covers the spread.
When you increase/decrease the bow weight you still have to tune the arrow to that weight.
When you increased you should have seen the arrow striking further right or even spraying the target area.
(depending on the amount of increase)
Broadheads will pick up tune problems faster than field points and that is why you must always finish tuning with broadheads.....to fine tune.
At 67# @ 27" you are under spined with the 40/60 shafts.
My suggestion would be to back that bow down to 62# (60 would be better) and go with it till season is over.
Keep in mind that bow weight has nothing to do with killing......it's all about shot placement
Now....on to the jig....
I don't like the Blitz jig....never have
Not saying that it's not a good jig.....it's just not an easy jig IMO
I'd suggest the Graying jig for around $34.
But....since you are trying to use this one....
Make sure that the clamp that holds the rear of the feather is center of the shaft.
You can do this visually by looking down on the clamp while it is empty and mounted and be pretty darn close.
Before you glue the feather , put it in the clamp and set the clamp against the shaft to see that it is making good contact on the rear and front of the feather.
You may find that leaving the feather slightly extended past the mouth of the clamp will make a better fit more times than not.
When you fit the dry feather against the shaft,do it gently and when you are satisfied with the fit , apply the glue and firmly (but not forcefully) apply the feather with the clamp.
I suggest super glue gel as it does not allow the feather to move much after it makes contact.
Super glue also helps beat the normally quick removal of the clamp blues as the builder anctiously removes the clamp to make sure everything is o.k. (big no no)
As to removal...
I use the flat of a knife to burnish the glued portion away.
Sort of like sanding.
Don't try and remove the feather with an angled slice as you can cut into the fibers of the arrow and ruin it.
As to the Blazers...
If thats what you are comfortable with then use them.
The Razor sharks shouldn't really care as long as the bow is tuned