fork oil change

when i got my forks springs replaced i was recommended using a heavier weight oil.
now due to fundage i dont really wanna take it to the mechanic so was wondering if i just stuck a syringe in and drew out as much oil as possible then refill with heavier a weight. i would make sure i remove the same amount from each fork leg so the weights should be the same after.
and i am not to worried about removing every last drop of oil as it was only replaced a few weeks ago.
Do you think this would be ok?
Also to do this would i just need to undo the caps on top of the forks?

[Spiderman]

In therory, yes you can. However i'd love to know where you are gonna get a long enough syringe from. Ive been looking for a decent sized one for ages.
I guess you could add a length of rubber tubing to the end of the syringe tho and use that.
And yes, you will need to take the caps off the tops of the first to do this.
HTH.

was gonna go for rubber tubing on the end.
mind you any ideas what size sockets for the cap i thought it was 22mm but that dont fit, got a 24mm spanner which does seems a bit loose so maybe 23mm.
should the caps be hard to undo?
had a crack at them with the spanner and they didnt seem to want to undo

I changed my springs/oil on Friday. It was pretty painless and easy. Removed the forks, removed the caps, springs, washers, spacers and let them drain for an hour into a measuring jug. After the hour 950ml of the 980ml had drained and I thought that was within an acceptable margin of error that all the oil had drained out leaving nothing but a fine film on the inner fork Walls.
The new springs went in, along with new 15wt oil and as most people would the bike has been transformed.