smoking malt

I'm interested in making a smoked porter later this year and I'd like to smoke my own malt, if possible. Well, technically I want to use a friend's smoker to do this (he smokes meat as a hobby). But I'd like to take advantage of any experience you guys might have on the subject. How long should the malt be smoked?

I took a look at this thread:
https://www.homebrewtalk.com/f11/dedicated-malt-smoker-25644/

And used the search to find other threads on the subject, but I wasn't able to find this kind of information.

I have a smoked porter recipe in the data base. I have a link in there to a BYO article about smoking your own grains. I use those guidelines and have had great success.

Actually, it seems they have removed that article from their database.... bummer.

I'm surprised by how little smoking time is required. And smoking nearly 100% of your malt is pretty impressive (I was thinking 33-50%).

I'll have to see if I can find back issues of BYO...