I don't see how the SAI affects the air filter getting mucky, the exhaust gas is causing air to be sucked from the airbox via the reeds and solenoid, not blowing into it.

Here are the main bits of a liner puller I made a decade ago.  Imagine the lower disc towards the top of the liner with the rubber thingy placed on top of it around the top of it inside the liner and the tapered disc squashing it somewhat by screwing a nut onto it to grip the liner after the oil ect had been cleaned off.  Then imagine 2 smallish blocks of wood about 5cm high with another flat piece across the top with a hole in it hole for the threaded bolt to pass through so that a washer and nut could be fitted in order to act as a puller.  Got it???



The other bolt and flat washer is what's needed to hold the liners in place after fitting 5 or 6 needed.

Thanks Grouchy. Well it's all a bit of classic over-think perhaps. I suspect I dont need to spend $56 + air freight from Oz to still wind up with a dirty filter. (It's got to be blowby?)

Does your air filter get dirty in a short time? Less than 1000 miles?

I found a set of plates 3 or 4 years ago but can't remember where. (Oldtimers disease).     

Just did a quick search and found these, but seem expensive.....

https://ratedrparts.com.au/products/triumph-sprint-1050-st-gt-ais-blanking-plates-smog-block-off-eliminator_304433136809_?pr_prod_strat=use_description&pr_rec_id=0ba532f6d&pr_rec_pid=7982373863678&pr_ref_pid=7982374289662&pr_seq=uniform

I also recall someone tapping the the nipples and sealing bolts in place, but angryrooster's  method  seems much easier.

FWIW Dave, I blocked mine and honestly couldn't tell a difference in performance or discoloration of the filter. Ive got a BMC filter in mine.   

Now sold thank you